External Data storage in Shiny apps - r

Question

I am developing a shiny application which save the data entered on the user interface. I have refered the url on shiny rstudio page so by using this page, the code i have written is as mentioned below:
outputDir <- "C:\\Users/dell/Desktop/"
saveData <- function(data) {
data <- t(data)
fileName <- sprintf("%s_%s.csv", as.integer(Sys.time()), digest::digest(data))
write.csv(
x = data, sep = ",",
file = file.path(outputDir, fileName),
row.names = FALSE, quote = TRUE
)
}
loadData <- function() {
files <- list.files(outputDir, full.names = TRUE)
data <- lapply(files, read.csv, stringsAsFactors = FALSE)
data <- do.call(rbind, data)
data
}
library(shiny)
fields <- c("name", "staff_name")
shinyApp(
ui = fluidPage(
titlePanel("attendance System"),
DT::dataTableOutput("responses", width = 300), tags$hr(),
textInput("name", "Accession Number", ""),
selectInput("staff_name", "Staff Name",
c("Rajiv" = "RT",
"Arvind " = "AKS",
"Ashutosh " = "AS")),
actionButton("submit", "Submit")
),
server = function(input, output, session) {
formData <- reactive({
data <- sapply(fields, function(x) input[[x]])
data
})
observeEvent(input$submit, {
saveData(formData())
})
output$responses <- DT::renderDataTable({
input$submit
loadData()
})
}
)
The above code create a new file for each entry. I am looking for a single file in which all entry to be added.

Answer 1

This will give you a unique file name based on time of save and content of the file:
fileName <- sprintf("%s_%s.csv", as.integer(Sys.time()), digest::digest(data))
You can give it a single name like:
fileName <- 'input_bu.csv'
Like #ismirsehregal, I'd recommend bookmarking for this though.

Answer 2

after looking various solutions. I reached at below code to save the data in a single file as it is entered.
library(shiny)
outputDir <- "C:\\Users/dell/Desktop/"
saveData <- function(data) {
data <- as.data.frame(t(data))
if (exists("responsesiq")) {
responsesiq <<- rbind(responsesiq, data)
} else {
responsesiq <<- data
}
fileName <- "test_igntu.csv"
write.csv(
x = responsesiq, sep = ",",
file = file.path(outputDir, fileName),
row.names = FALSE, quote = TRUE
)
}
fields <- c("acc", "staff_name")
shinyApp(
ui = fluidPage(
titlePanel("Attendance System"),
DT::dataTableOutput("responsesiq", width = 300), tags$hr(),
numericInput("acc", "AccNumber", ""),
selectInput("staff_name", "Staff Name",
c("Rajiv" = "RT",
"Arvind" = "AKS",
"Ashutosh" = "AS")),
actionButton("submit", "Submit")
),
server = function(input, output, session) {
# Whenever a field is filled, aggregate all form data
formData <- reactive({
data <- sapply(fields, function(x) input[[x]])
data
})
# When the Submit button is clicked, save the form data
observeEvent(input$submit, {
saveData(formData())
})
}
)